If you are in PA, a tune by https://www.jdscycleworks.com/ will ensure every pony in there is untapped.

 

A 110" with even moderate heads to match that cam should hit 120 no problem.

 

120hp?
What torque number are you looking for?

In that state of tune, cooling will be a challenge.

Well, that, and reliability.

Amazing to think to get to that power level (120,) that components from 10 different companies are needed. Sure hope they all play well with each other. Good luck with your experiment.

 

120 hp in a 110" engine is a simple task.
New Orleans HD tuned one of our 110"s not long ago with our Stage III Super-Tour Heads, and S&S .570 cams.
That pushed up past 120, at only 10.25 compression.
Scott

 

Just think of it as one cube per HP -Thats EZ
How?
110 with 10.5 is EZ.
120?
With proper squish and cam some mild head work should be simple! All you are only asking 1.10 per cube.
POC
(Piece of cake)

 

110" combo's have shown at/near 130/130 in both carb, and EFI.
As long as you have the cylinder head working correctly, proper cam selection, compression, intake and pipe, they'll do just that.
Scott

 

 

120 out of a 110 is pretty easy,do your homework,a lot of kits out there WAY cheaper (& better) than zippers.that said,you should really plan a build to give what fits your riding style & not to just "get over 120 hp"

 

SS drop on 110 + S&S585 + WFO heads + HPI58 + 5.3 inj + good clutch+good pipe+ good tuner + good tune looked like this